The effect of farfield and nearfield earthquakes on the seismic behavior of micropile group in loose and dense granular soils

Document Type : Research Article

Authors

1 M.Sc. of Geotechnical Engineering, Department of Civil Engineering, Shahrood University of Technology

2 Civil Engineering Faculty Dean, Shahrood University of Technology, Shahrood, Iran

Abstract

Studying the performance of micropile system as an effective, practical and affordable method for seismic retrofitting of the site and foundation and considering the different characteristics and effects of nearfield and farfield earthquakes on structures, justifies the need to study the performance of micropile group under nearfield and farfield earthquakes. In this research, using Opensees software, two types of loose (Dr =40%) and dense (Dr = 80%) granular soils with elastoplastic behavior and two reinforcement models including vertical and inclined micropiles with elastic behavior and concrete material were affected by three sets of farfield and nearfield earthquakes due to the shear wave velocity of the site (Vs30). The responses of the micropile group, including horizontal displacement, acceleration and internal forces, were studied and compared and important results were presented to use the micropile group in order to seismic retrofitting of areas close to and far from the epicenter. The results showed that the effect of near-fault records significantly increases the horizontal displacement, especially in the loose granular site. The increase in lateral displacement due to near earthquakes compared to far earthquakes is 125% and 124% for the vertical and inclined micropile group in the loose granular structure and 15% and 13% for the vertical and inclined micropile group in the dense granular site, respectively. Also, the inclined micropile group shows almost similar performance in controlling horizontal displacements and better performance in controlling internal forces than the vertical micropile group.

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Main Subjects

References

[1] D.A. Bruce, I. Juran, Drilled and Grouted Micropiles: State-of-Practice Review, Volume I: Background, Classifications, Cost  (1997).
[2] M. Sadek, S. Isam, Three-dimensional finite element analysis of the seismic behavior of inclined micropiles, Soil Dynamics and Earthquake Engineering, 24(6) (2004) 473-485.
[3] M. Sadek, I. Shahrour, Influence of the head and tip connection on the seismic performance of micropiles, Soil Dynamics and Earthquake Engineering, 26(5) (2006) 461-468.
[4] S. Isam, A. Hassan, S. Mhamed, 3D elastoplastic analysis of the seismic performance of inclined micropiles, Computers and Geotechnics, 39 (2012) 1-7.
[5] A. Ghorbani, H. Hasanzadehshooiili, E. Ghamari, J. Medzvieckas, Comprehensive three dimensional finite element analysis, parametric study and sensitivity analysis on the seismic performance of soil–micropile-superstructure interaction, Soil Dynamics and Earthquake Engineering, 58 (2014) 21-36.
[6] M.C. Capatti, F. Dezi, M. Morici, Field tests on micropiles under dynamic lateral loading, Procedia Engineering, 158 (2016) 236-241.
[7] M. Capatti, D. Roia, S. Carbonari, F. Dezi, Micropile foundation subjected to dynamic lateral loading, Procedia engineering, 199 (2017) 2324-2329.
[8] H.J. Mashhoud, J.-H. Yin, A.K. Panah, Y.F. Leung, Shaking table test study on dynamic behavior of micropiles in loose sand, Soil Dynamics and Earthquake Engineering, 110 (2018) 53-69.
[9] J.P. Stewart, S.-J. Chiou, J.D. Bray, R.W. Graves, P.G. Somerville, N.A. Abrahamson, Ground motion evaluation procedures for performance-based design, Soil dynamics and earthquake engineering, 22(9-12) (2002) 765-772.
[10] M. Erdik, E. Durukal, A hybrid procedure for the assessment of design basis earthquake ground motions for near-fault conditions, Soil Dynamics and Earthquake Engineering, 21(5) (2001) 431-443.
[11] J.D. Bray, A. Rodriguez-Marek, Characterization of forward-directivity ground motions in the near-fault region, Soil dynamics and earthquake engineering, 24(11) (2004) 815-828.
[12] A. Moustafa, I. Takewaki, Deterministic and probabilistic representation of near-field pulse-like ground motion, Soil Dynamics and Earthquake Engineering, 30(5) (2010) 412-422.
[13] T. Liu, Y. Luan, W. Zhong, A numerical approach for modeling near-fault ground motion and its application in the 1994 Northridge earthquake, Soil Dynamics and Earthquake Engineering, 34(1) (2012) 52-61.
[14] E. Ahmadi, F. Khoshnoudian, Near-fault effects on strength reduction factors of soil-MDOF structure systems, Soils and Foundations, 55(4) (2015) 841-856.
[15] T.G. Cork, J.H. Kim, G.P. Mavroeidis, J.K. Kim, B. Halldorsson, A.S. Papageorgiou, Effects of tectonic regime and soil conditions on the pulse period of near-fault ground motions, Soil Dynamics and Earthquake Engineering, 80 (2016) 102-118.
[16] N. Yeganeh, B. Fatahi, Effects of choice of soil constitutive model on seismic performance of moment-resisting frames experiencing foundation rocking subjected to near-field earthquakes, Soil Dynamics and Earthquake Engineering, 121 (2019) 442-459.
[17] W. Xie, L. Sun, Assessment and mitigation on near-fault earthquake wave effects on seismic responses and pile-soil interactions of soil-pile-bridge model, Soil Dynamics and Earthquake Engineering, 143 (2021) 106596.
[18] H.M. Moghaddam, M. Keramati, A. Ramesh, R. Naderi, Experimental Evaluation of the Effects of Structural Parameters, Installation Methods and Soil Density on the Micropile Bearing Capacity, International Journal of Civil Engineering,  (2021) 1-13.
[19] S. Mazzoni, F. McKenna, M.H. Scott, G.L. Fenves, OpenSees command language manual, Pacific Earthquake Engineering Research (PEER) Center, 264 (2006) 137-158.
[20] G. Lanzo, A. Pagliaroli, B. D’Elia, Numerical study on the frequency-dependent viscous damping in dynamic response analyses of ground, Earthquake Resistant Engineering Structures IV, WIT Press, Southampton, Boston,  (2003) 315-324.
[21] D. Park, Y.M. Hashash, Soil damping formulation in nonlinear time domain site response analysis, Journal of Earthquake Engineering, 8(02) (2004) 249-274.
[22] S. Kramer, Geotechnical earthquake engineering, Prentice Hall Upper Saddle River, New Jersey,  (1996).
[23] Z. Karimi, S. Dashti, Numerical and centrifuge modeling of seismic soil–foundation–structure interaction on liquefiable ground, Journal of Geotechnical and Geoenvironmental Engineering, 142(1) (2016) 04015061.
[24] J. Lysmer, R.L. Kuhlemeyer, Finite dynamic model for infinite media, Journal of the Engineering Mechanics Division, 95(4) (1969) 859-877.
[25] K. McManus, J. Turner, G. Charton, Inclined reinforcement to prevent soil liquefaction, in:  Proceedings of the Annual NZSEE Technical Conference, Citeseer, 2005, pp. 523-533.
[26] Z. Cheng, B. Jeremić, Numerical modeling and simulation of pile in liquefiable soil, Soil Dynamics and Earthquake Engineering, 29(11-12) (2009) 1405-1416.
[27] R. Verdugo, F. Ochoa-Cornejo, J. Gonzalez, G. Valladares, Site effect and site classification in areas with large earthquakes, Soil Dynamics and Earthquake Engineering, 126 (2019) 105071.
[28] A.T. Council, U.S.F.E.M. Agency, Quantification of building seismic performance factors, US Department of Homeland Security, FEMA, 2009.
[29] A. Komak Panah, H. Jalilian Mashhoud, J.-H. Yin, Y. Fai Leung, Shaking table investigation of effects of inclination angle on seismic performance of micropiles, International Journal of Geomechanics, 18(11) (2018) 04018142.
Amirkabir Journal of Civil Engineering
Volume 54, Issue 4
July 2022
Pages 1483-1502

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